For the diagnosis of B-ALL, a broad leukemia marker panel was applied, including common progenitor markers (CD34, HLA-DR), panleucocytic marker (CD45), B-cell markers (CD10, CD19, CD22, cyt IgM, cyt CD79α, Kappa, Lambda), T-cell markers (CD2, CD3, CD4, CD5, CD7, and CD8), and myeloid markers (CD13, CD14, and CD33). The gene discussed is CD7; the disease is precursor B-cell acute lymphoblastic leukemia.